Developer productivity refers to how productive a developer is during a specific time or based on any criteria. It can be measured using various methods such as the SPACE and OKR frameworks. The SPACE framework focuses on satisfaction, performance, activity, communication, and efficiency while OKR measures personal objectives and key results. However, measuring developer productivity only through specific metrics can be hazardous as it may not capture all aspects of a developer's work or their surrounding environment. Therefore, organizations should use a combination of these methods to gauge developer productivity effectively.